151.3400 should be the one in use for D11. Search the FCC database for that frequency and using a radius search from your point to find the closest sites. I'm seeing sites in Yanceyville, Chapel Hill, Oxford, Oak Hill, & Clayton. Reference KSJ271, WQJD752, & WQJD747 for more details. I imagine the NCFS has quite a few VIPER radios to interop with Wake County and the surrounding area. I know D12 has a few portables down here for Mecklenburg County.
What do you have down for D5 & D6? I need to overhaul the NCFS listing at some point. If anyone can confirm what frequency and tone they're hearing for their respected districts, I'd appreciate it if you posted here.